The novel technology for reservoir stimulation: in situ generation of carbon dioxide for the residual oil recovery

Abstract

The gas and chemical flooding for reservoir stimulation with residual hydrocarbons reserves are highly relevant problem of current oil and gas recovery strategy. The objective of this paper is laboratory study and field implementation of new gas-EOR technology—in situ carbon dioxide generation technique for CO2-liquid slug formation under oil displacement, increasing the reservoir sweep efficiency and residual oil recovery. This paper presents a summary of a wide range of laboratory tests conducted on different core samples and chemical compositions. Several physical and hydrodynamic phenomena of in situ CO2 generation in highly permeable zones of a porous medium have been investigated as a part of complex study, which involved laboratory tests on the field-scale industrial technology applications, determination of optimal concentrations of foaming agents and inhibiting additives in gas-releasing solutions, etc. The results of laboratory experiments showed that the incremental recovery ranged between 30 and 35% oil original in place. The unique results of the field implementation provide developing an optimal technological scheme of reservoir stimulation with residual oil reserves both onshore and offshore oil fields. Technology of in situ CO2 generation was applied on the group of wells on Penglai offshore oil field (Bohai Bay). Incremental oil production for field operation was 37,740 bbl of crude oil. Theoretical and laboratory studies, as well as the outcomes of industrial implementation of a new method of residual oil recovery, using a CO2-slug confirm technology and economic profitability of the proposed solution.

Modelling of Internal Transformations of Gas Phase in Porous Media

“…Under the same reservoir conditions, the density and viscosity of carbon dioxide are much lower than those of oil. Under certain special thermobaric conditions, carbon dioxide can also be in a supercritical state (Panahov et al, 2021;Mahmoodpour et al, 2023). In the case of two fluids in a separate pore due to the free pressure drop gradient (Ferer & Smith, 1994) is defined as:…”

Toward Understanding the Effect of Electromagnetic Radiation on In Situ Heavy Oil Upgrading and Recovery: Background and Advancements

“…The production of heavy oil involves various challenges due to its physical properties. Its high viscosity makes it resistant to flow, requiring specialized techniques for extraction [4,5]. Additionally, heavy oil often contains higher amounts of sulfur, metals, and other impurities, which can complicate refining [6].…”

“…The recovery of heavy oil involves several methods that aim to reduce the viscosity of the crude oil, allowing it to flow more easily through wells and pipelines. Hence, some common techniques utilized in heavy oil recovery include thermal methods [5], such as steam [10] or gas [11] injection and in situ combustion [12], as well as nonthermal methods like chemical flooding [13]. Thermal methods involve heating the reservoir to reduce the viscosity of the heavy oil [14].…”

Modelling of colmatant mass transfer during in situ gas generation process

“…These conglomerates formed deep along the strike of the reservoir on the walls of pore channels and in the free space of pores lead to a local increase in flow resistance due to narrowing (retardation) and partial or complete blocking of individual pore channels, which in turn leads to a change in the direction of filtration flow and to an increase in reservoir sweep efficiency [9]. It should also be noted that some of the formations interact with the flowing fluid.…”